So, the values I used were just wrong and it should work as wired once I change those?
Thanks man!! Did you just put that together?
So in the case of the 2003 the input voltage just controls the transistor switching, and when switched the output pin is tied to ground? So there is no way for the ic to output voltage on the output pins?
On a side note, connecting the outputs of the 4017 directly to the input relay board does work but the output voltage is pulled down from 12v to 8.5v when a relay in engaged. Is this likely to create unreliable functioning or damage?
On a side note, connecting the outputs of the 4017 directly to the input relay board does work but the output voltage is pulled down from 12v to 8.5v when a relay in engaged. Is this likely to create unreliable functioning or damage?
I did, and its my first ever YouTube vid as well
I see a lot of the circuits don't show current limiting resistors for the LED's and I think they should. To not do so relies 100% on the short circuit ability/protection of the chip, and also when driving LED's directly it limits the maximum voltage that the output pin can rise to (the LED forward voltage). These were 3k3's. You wouldn't need these interfacing directly to another logic input though as they present essentially no load.
Thanks Mooly, it worked like a charm. A pull down resistor only did allow it to now count, but the results were unstable. your debounce circuit does it beautifully though
Now I can't get the 2003 working and it looks like that might not be the right solution.
If the 4017 is working to drive the relay board on it's outputs alone is there a problem just using that?
Now I can't get the 2003 working and it looks like that might not be the right solution.
If the 4017 is working to drive the relay board on it's outputs alone is there a problem just using that?
excellent.
If you can get enough drive current from the 4017 and it works then I would say its OK. You are limited though to just a few milliamps.
Edit... the data sheet shows the official value to be small.
It's working fine so far. Even with indicator leds for the different inputs in the circuit as long as the resister is above about 600. I'm using 4.7k but may go higher as they're still a little too bright.
Is there a way to get it to remember the last input used? I can keep the board powered at 12v when in standby if that's ok? Or a cap on the b+?
If you leave it powered, it "should" hold the last setting you or the cat picked.
If you can isolate ALL "power loads", LEDs and relays, and break the pushbutton connection, the CD4017 alone can run and hold-state "forever" on a small battery or a super cap (well, until the batt self-rots or the supercap discharges). The hold-up supply can probably be 3V, two AA cells; though IIRC that's close to the limit for standard CMOS and a simple diode isolator adds a half-volt; we tended to 4.5V-6V standby power.
If you really wanna know, Lancaster's "CMOS Cookbook" has ideas. But that would be like reading a complete set of Julia Child to bake a potato.
It as PRR says. You can keep CMOS powered indefinitely as power consumption when the logic is idle is essentially zero.
I did just that here. This uses three 4017's for a variety of push button operations such as input select, filters etc and used a 2.4v NiCad battery (middle board) to keep it all alive.
Its a slightly different arrangement to yours and used a low freq oscillator to clock the 4017's so that the button presses don't have to be sequential, you just press the one you want.
I did just that here. This uses three 4017's for a variety of push button operations such as input select, filters etc and used a 2.4v NiCad battery (middle board) to keep it all alive.
Its a slightly different arrangement to yours and used a low freq oscillator to clock the 4017's so that the button presses don't have to be sequential, you just press the one you want.
Attachments
As it is now the board is on a delay circuit to prevent turn-on/off transients but.... that mutes the inputs
. I had a brainfart there and will have to move that circuit so it mutes the outputs and will not delay the turn on of the 4017 or I could delay both the 4017, input relays and output with an extra relay. I can also leave it powered or turn it off during standbyThe only issue with leaving the board powered at 12v is that I think the current input indicator would stay lit at all times which isn't that big a deal to me.
How would I break the push button connection? It's a momentary switch so it breaks automatically or do I also need to break the debounce to prevent drain through the RC circuit?
The 100k and 10k are in series across the rail and so draw a small but continuous current.
At 10 volts supply it is just 0.09 milliamps. Not a lot
You could scale each resistor by 10 (so 1Meg and 100k) and reduce the cap by a factor of 10 to cut that to 0.009 milliamps.
The LED's would be a problem though as one of them is always on.
If you add CMOS buffers to the 4017 outputs then you can run the chip from a battery/supercap backup supply. When the power goes off the LED's and buffer power down but the 4017 is kept alive by the battery/cap.
At 10 volts supply it is just 0.09 milliamps. Not a lot
You could scale each resistor by 10 (so 1Meg and 100k) and reduce the cap by a factor of 10 to cut that to 0.009 milliamps.
The LED's would be a problem though as one of them is always on.
If you add CMOS buffers to the 4017 outputs then you can run the chip from a battery/supercap backup supply. When the power goes off the LED's and buffer power down but the 4017 is kept alive by the battery/cap.
The 100k and 10k are in series across the rail and so draw a small but continuous current.
At 10 volts supply it is just 0.09 milliamps. Not a lot
You could scale each resistor by 10 (so 1Meg and 100k) and reduce the cap by a factor of 10 to cut that to 0.009 milliamps.
The LED's would be a problem though as one of them is always on.
If you add CMOS buffers to the 4017 outputs then you can run the chip from a battery/supercap backup supply. When the power goes off the LED's and buffer power down but the 4017 is kept alive by the battery/cap.
Ok thanks. I'll take a look at it when I get time and see if I can figure anything out.
What does the chip do when power is disconnected? Revert to Q0 or no output? I don't remember
Last question, the preamps basically finished and is working well. But I don't understand how you mute the output. I know you shunt them to ground usually but how do you do that with one relay and keep the channels separate? And of course I have four channel outs
I've delayed applying plate current until the tubes are warm so no squealing but I still get on/off transients
I've delayed applying plate current until the tubes are warm so no squealing but I still get on/off transients
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.